Knockdown and portable combination form and traveler for constructing inclined concrete arches



Dec. 14, 1926. 1,610,570

KNOCKDOWN AND PORTABLE COMBINATION FORM AND TRAVELER FOR C. P. MILBURN CONSTRUGTING INCLINED CONCRETE ARCHES 1924 4 Sheets-Sheet 1 Filed Oct. 16

I rwaniar'. Charles Dec. 14 1926.

C. P. MILBURN KNOCKDOWN AND PORTABLE COMBINATION FORM AND TRAVELER FOR CONSTRUCTING INCLINED CONCRETE ARCHES Filed Oct. 16 192 4 Sheets-Sheet 2 L f 21% 4 T e f M l 4 F I l I? 14L! 5 79 l5 3 a L Q I I l /9 v 2, Q1 .1410

. v x5 W Inueizlor wz'iness CharlesPM'Zurn I RUM/WW9 Dec. 14, 1926. 1,610,570 C. P. MIL RN KNOCKDOWN AND PORTABLE COMBINAT N FORM AND TRAVELER FOR GONSTRUCTING INCLINE-D CONCRETE ARCHES Filed Oct. 16. 1924 4 Sheets-Sheet 5 C'haf'les 1 W6 um Dec. 14, 1926.

C. P. MILBURN ATION FORM AND TRAVELER FOR INED CONCRETE ARCHES l6 192 4 Sheets-Sheet 4 KNOCKDOWN AND PORTABLE COMBIN CONSTRUCTING INCL Filed Oct.

Patented Dec. 14, 1926.

, UNITED STATES CHARLES P. MILBUR'N, OF LOS ANGELES.

1,610,570 PATENT OFFICE.

CALIFORNIA. ASSIGNOR OF ONE-.HALF TO BENT BROTHERS, INC., OF LOS ANGEL-ES, CALIFORNIA, A CORPORATION OF CALI- FORNIA.

KNOCKDOWN AND PORTABLE COMBINATION FORM AND TRAVELER FOR CONSTRUCT- ING INCLINED CONCRETE ARCHES.

Application filed October 16, 1924. Serial No. 743,993.

This invention is applicable to various uses and is particularly adapted for use in the construction of inclined arches of upwardly diminishing thickness.

In arches of this character it is customary to maintain for each setting, a predetermined radius for the extrados and an expanding radius for the intrados, thus allowing the thickness of the dam to gradually diminish as the structure approaches the top. Said predetermined radius may be constant throughout the arch.

An object of this invention is to reduce the expense of building concrete walls and arches; and the invention is applicable to the construction of arches, irrespective of the angle of the axis thereof to the horizon.

An object of the invention is to make provision whereby the forms for supporting the wet concrete may; be. easily movable from station to station as the work proceeds.

Another object is to make provision for constructing substantially vertical arches of various radii. I

My invention comprises a system of forms for supporting wet concrete for the construction of vertical walls and inclined from vertical arches, either convex or concave, and said form is made up of parts and principles, some of which are old and others entirely new.

The invention comprises certain parts and combinations of parts, and the assembly of the various parts constitutes a Working whole.

In this invention I have provided a system of mold structure forms comprising an assembly or combination of trusses to form a vehicle which I calla traveler, and which aligns and supports the inside or intrados forms, and in combinationwith a set of panels or built-in-place extrados forms, between buttresses or other confining walls a complete mold for molding the concrete for the arch.

An object of the invention is to provide a system of forms adapted to the construction of high walls andarches found in large arch dams.

An objectof the invention is to provide for changing the radius of the form at will and for determining the radius of any intrados form in any relative positions.

The invention is broadly new, basic and pioneer in that I have produced a novel form, the parts of which constitute a vehicle that may be moved up or down the stripped intrados form to a new position when it is to be re-assembled for the next concrete our.

A further feature is to provide a traveler supported scaffold upon which the operators may be supported while getting at the intrados form; the scafiold travelling with the traveler and thus making a permanent working platform at all times.

Another feature of the invention consists in the construction of the extrados forms in elliptical panels terminating at the upper end in a horizontal plane, that arch themselves from supporting wall to supporting wall carrying the concrete arch, when completed, in such a manner as to act in unison with'the intrados forms, thus providing the means of carrying 'many tons of concrete without undue distortion, and relieving the traveler of this duty, and whereby the weight of the device is cut sufficiently to allow moving it with ordinary mechanical means.

Another object is to make provision whereby horizontal pouring clear across the arch or arches of the structure may be effected at one time, thus forming a concrete surface easy to clean and prepare for the next pour.

Other objects, advantages and features of invention may appear from the accompanying drawings, the subjoined detail description and the appended claims.

The accompanying drawings illustrate the invention.

. Figure 1 is a fragmental view of the upstream side of a dam in course of construction with my novel form for constructing inclined arches in place.

Fig. 2 is a perspective view of the downstream face of the dam, showing specimens of the invention as the same may appear in use in constructing a multiple inclined arch dam with buttresses partly completed; the near one of the arches and the traveler form thereon being shown in vertical midsection; three other arches and buttresses being. partly completed, and three other buttresses being completed, two with their forms thereon and one freed from its form.

Fig. 3 is a fragmental view on a larger scale than Fig. 2, illustrating the invention as applied in constructing an inclined arch between two buttresses which are shown, together with the incompleted arch; and the intrados form and its support is shown in place. The scaffold planks are omitted.

Fig. 4 is a face view of,an adjustable knockdown intrados form corresponding to the forms shown in Figs. 2 and 3. The initial osition is shown in dot and dash lines. olid lines indicate a partially expanded position to reduce the thickness of the arch, and broken lines indicate a further expansion of the segments to further reduce the thickness of the arch as the wall approaches completion.

Fig. 5 is a fragmental sectional elevation on line indicated at x5, Fig. 3, showing the traveler and form in position for use in constructing an inclined arch, a fragment of which, together with a fragment of one of its buttresses is shown.

Fig. 6 is a fragme-ntal perspective View showing in vertical central section a slanting arch mold partly filled with concrete and showing the extrados and int-rados forms in place.

The traveler A comprises trusses a which may be constructed in any desired manner, and are shown in the drawings as consisting of the chord 1, struts 2 and segments 3, which may be of any desired built-up construction, as shown.

The chord and segments of the truss are provided with radial ways 4 for adjustable struts 5 and adjustable sectional segments 6 fastened to the adjustable struts by suitable means as the adjustable bolts passing through slots 8; each adjustable segment being carried by a plurality of adjustable radial struts 5.

. Means are provided for fixing the radial struts 5 in various positions relative to the segment of the fixed truss, and in the drawings such means are indicated by the holes 9 in the adjustable struts, holes 10 in the fixed segment, and pins 11 adapted to pass through the holes 10 and 9; and the adjustable segment sections are connected. to the adjustable struts by adjusting means consisting of bolts 7 and slots 8; said slots extending longitudinally of the section segments.

The adjustable segments of the adjustable trusses support the intrados form 12, which may be formed in any suitable way as by a plurality of panels 13.

The trusses a are connected together by any suitable means as the truss-connecting struts 14: and 15, and the tie rods 16, 17, 18.

19 indicates brackets fixed to a support in any suitable way as by the bolts 20 in buttresses B, and in turn supporting skidways 21 upon which the traveler A is movably supported.

22 indicates a platform supported from the traveler by means of a bolt 23 at the lower end, and an adjustable hanger 24 at the upper end; said hanger being shown with holes to receive pins 26 inserted through holes 27 in the sill 28 of the platform.

The extrados forms 29 are of any prede termined radius, thev same being constant from bottom to top of the arch 30; and said cxtrados forms terminate at top and bottom in horizontal planes and have elliptical contours at top 31 and bottom 32.

The intrados form composed of the fixed and adjustable trusses and the panels may be of any approved length from bottom to top, and the ex'trados forms correspond in lengt thereto.

In practical operation the buttresses B are first built to a height suflicient at least to carry the traveler and may be built to any height desired above that. Then the extrados and intrados forms of the mold are spaced a predetermined distance apart at the base of the proposed arch and are set at the predetermined inclination or angle to the horizon, and are supported by the but.- tresses, the intrados form approaching the extrados form upwardly, and said forms are tied together by any desired means as the wires or rods 33. The aggregate is then poured between the forms or otherwise put in place in any usual manner, and when the top of the aggregate reaches the level top of the extrados and intrados forms it is allowed to set and the forms are then stripped from the arch thus made and are then moved upward to a new station where the operation is repeated.

In practical operation the intrados and extrados forms will be set in position for forming the. lower part of the inclined arch and will be spaced apart in accordance with the desired thickness of the arch at that level.

When the aggregate has been placed in the usual manner and allowed to set, and the forms stripped from the arch, the forms will be brought into a higher position and fixed in the usual way as by the wires 33 placed in the arch.

After the concrete is setthe adjustable struts are released from the fixed truss and are drawn in, thus withdrawing the panels of the traveler from the concrete arch: and then the connect-idns 33 are cut and the extrados and intrados forms are raised to. a new level and brought into positions for molfiling the next section or layer of the arc At this stage the scaffold platform 22 is secured in position as previously described, and the workmen stand on the platform.

By the use of this platform the workmen again remove the pins 11 thereby allowin the radial struts 5 to be pulled back. The forms are collapsed then in position for the traveler to be hoisted to its next setting.

Then the -adjustable struts are thrust outward to bring the panels into the position for continuing the arch upward at a reduced thickness.

The work is thus proceeded with until the required height is reached.

The intrados forms, trusses and traveler,

are raised by sliding the same up the skids by any suitable means, as block and tackle, not shown.

The extrados forms will be slid up from the set arch and will be supported in place by any suitable means as block and tackle, not shown.

' When the arch hasbeen completed and the forms removed, the nuts on bolts may be taken off and the brackets 19 may be removed from the buttresses for use on another structure.

I claim.

1. In combination with buttresses; of an extrados form of a predetermined radius and horizontal top and bottom and elliptical contours at said topand bottom; an intrados form composed of trusses, said trusses carrying radial struts and expanding segments, said struts supporting said segments; all forming a carrier to support a plurality of panels which are adjustable to the changed radii of the carrier; and means to secure the two forms together between buttresses for the purpose of forming a mold for an upwardly inclined arch diminishing in thickness toward the top.

2. An intrados form comprising trusses, said trusses comprising chords, struts and segments, means to radially adjust said struts, adustable segments secured to said struts; and panels supported by said adjustable segments.

3. The intrados traveling form set forth comprising upper and lower trusses each 5. Theintrados supporting trusses comprising segments and a chord and struts adjustably connecting the segments and the chord; the segments being adjustable relative to each other.

6. The trusses for supporting an intrados.

form comprising a chord and segments provided with slots forming ways; struts extending through said ways; said struts and chords being provided with holes and pins for said holes to secure the struts in adjustable relation to the chord and segments.

7. An intrados form for the formation of arches between buttresses comprising inclined panels and trusses for supporting the panels said trusses being provided with means for changing the radius of the intrados form; brackets adapted to be secured to said buttresses; and skids parallel to the panels for guiding the form when the form is moved upward, said skids being secured to brackets secured to said buttresses.

8. The trusses for supporting an intrados form comprising a chord and segments provided with slots forming ways; struts extending through said ways; said struts and chords being provided with holes and pins for said holes to secure the struts in adjustable relation to the chord and segments, adjustable segments secured to said struts; and panels supported by said adjustable segments.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 6th day of October, 1923.

CHARLES P. MILBURN. 

